# frozen_string_literal: true

require_relative "../rubygems"
require_relative "dependency_list"
require_relative "package"
require_relative "installer"
require_relative "spec_fetcher"
require_relative "user_interaction"
require_relative "available_set"

##
# Installs a gem along with all its dependencies from local and remote gems.

class Gem::DependencyInstaller
  include Gem::UserInteraction

  DEFAULT_OPTIONS = { # :nodoc:
    env_shebang: false,
    document: %w[ri],
    domain: :both, # HACK: dup
    force: false,
    format_executable: false, # HACK: dup
    ignore_dependencies: false,
    prerelease: false,
    security_policy: nil, # HACK: NoSecurity requires OpenSSL. AlmostNo? Low?
    wrappers: true,
    build_args: nil,
    build_docs_in_background: false,
  }.freeze

  ##
  # Documentation types.  For use by the Gem.done_installing hook

  attr_reader :document

  ##
  # Errors from SpecFetcher while searching for remote specifications

  attr_reader :errors

  ##
  # List of gems installed by #install in alphabetic order

  attr_reader :installed_gems

  ##
  # Creates a new installer instance.
  #
  # Options are:
  # :cache_dir:: Alternate repository path to store .gem files in.
  # :domain:: :local, :remote, or :both.  :local only searches gems in the
  #           current directory.  :remote searches only gems in Gem::sources.
  #           :both searches both.
  # :env_shebang:: See Gem::Installer::new.
  # :force:: See Gem::Installer#install.
  # :format_executable:: See Gem::Installer#initialize.
  # :ignore_dependencies:: Don't install any dependencies.
  # :install_dir:: See Gem::Installer#install.
  # :prerelease:: Allow prerelease versions.  See #install.
  # :security_policy:: See Gem::Installer::new and Gem::Security.
  # :user_install:: See Gem::Installer.new
  # :wrappers:: See Gem::Installer::new
  # :build_args:: See Gem::Installer::new

  def initialize(options = {})
    @only_install_dir = !options[:install_dir].nil?
    @install_dir = options[:install_dir] || Gem.dir
    @build_root = options[:build_root]

    options = DEFAULT_OPTIONS.merge options

    @bin_dir             = options[:bin_dir]
    @dev_shallow         = options[:dev_shallow]
    @development         = options[:development]
    @document            = options[:document]
    @domain              = options[:domain]
    @env_shebang         = options[:env_shebang]
    @force               = options[:force]
    @format_executable   = options[:format_executable]
    @ignore_dependencies = options[:ignore_dependencies]
    @prerelease          = options[:prerelease]
    @security_policy     = options[:security_policy]
    @user_install        = options[:user_install]
    @wrappers            = options[:wrappers]
    @build_args          = options[:build_args]
    @build_docs_in_background = options[:build_docs_in_background]
    @dir_mode = options[:dir_mode]
    @data_mode = options[:data_mode]
    @prog_mode = options[:prog_mode]

    # Indicates that we should not try to update any deps unless
    # we absolutely must.
    @minimal_deps = options[:minimal_deps]

    @available      = nil
    @installed_gems = []
    @toplevel_specs = nil

    @cache_dir = options[:cache_dir] || @install_dir

    @errors = []
  end

  ##
  # Indicated, based on the requested domain, if local
  # gems should be considered.

  def consider_local?
    @domain == :both || @domain == :local
  end

  ##
  # Indicated, based on the requested domain, if remote
  # gems should be considered.

  def consider_remote?
    @domain == :both || @domain == :remote
  end

  def in_background(what) # :nodoc:
    fork_happened = false
    if @build_docs_in_background && Process.respond_to?(:fork)
      begin
        Process.fork do
          yield
        end
        fork_happened = true
        say "#{what} in a background process."
      rescue NotImplementedError
      end
    end
    yield unless fork_happened
  end

  ##
  # Installs the gem +dep_or_name+ and all its dependencies.  Returns an Array
  # of installed gem specifications.
  #
  # If the +:prerelease+ option is set and there is a prerelease for
  # +dep_or_name+ the prerelease version will be installed.
  #
  # Unless explicitly specified as a prerelease dependency, prerelease gems
  # that +dep_or_name+ depend on will not be installed.
  #
  # If c-1.a depends on b-1 and a-1.a and there is a gem b-1.a available then
  # c-1.a, b-1 and a-1.a will be installed.  b-1.a will need to be installed
  # separately.

  def install(dep_or_name, version = Gem::Requirement.default)
    request_set = resolve_dependencies dep_or_name, version

    @installed_gems = []

    options = {
      bin_dir: @bin_dir,
      build_args: @build_args,
      document: @document,
      env_shebang: @env_shebang,
      force: @force,
      format_executable: @format_executable,
      ignore_dependencies: @ignore_dependencies,
      prerelease: @prerelease,
      security_policy: @security_policy,
      user_install: @user_install,
      wrappers: @wrappers,
      build_root: @build_root,
      dir_mode: @dir_mode,
      data_mode: @data_mode,
      prog_mode: @prog_mode,
    }
    options[:install_dir] = @install_dir if @only_install_dir

    request_set.install options do |_, installer|
      @installed_gems << installer.spec if installer
    end

    @installed_gems.sort!

    # Since this is currently only called for docs, we can be lazy and just say
    # it's documentation. Ideally the hook adder could decide whether to be in
    # the background or not, and what to call it.
    in_background "Installing documentation" do
      Gem.done_installing_hooks.each do |hook|
        hook.call self, @installed_gems
      end
    end unless Gem.done_installing_hooks.empty?

    @installed_gems
  end

  def install_development_deps # :nodoc:
    if @development && @dev_shallow
      :shallow
    elsif @development
      :all
    else
      :none
    end
  end

  def resolve_dependencies(dep_or_name, version) # :nodoc:
    request_set = Gem::RequestSet.new
    request_set.development         = @development
    request_set.development_shallow = @dev_shallow
    request_set.soft_missing = @force
    request_set.prerelease = @prerelease

    installer_set = Gem::Resolver::InstallerSet.new @domain
    installer_set.ignore_installed = (@minimal_deps == false) || @only_install_dir
    installer_set.force = @force

    if consider_local?
      if dep_or_name =~ /\.gem$/ && File.file?(dep_or_name)
        src = Gem::Source::SpecificFile.new dep_or_name
        installer_set.add_local dep_or_name, src.spec, src
        version = src.spec.version if version == Gem::Requirement.default
      elsif dep_or_name =~ /\.gem$/ # rubocop:disable Performance/RegexpMatch
        Dir[dep_or_name].each do |name|
          src = Gem::Source::SpecificFile.new name
          installer_set.add_local dep_or_name, src.spec, src
        rescue Gem::Package::FormatError
        end
        # else This is a dependency. InstallerSet handles this case
      end
    end

    dependency =
      if spec = installer_set.local?(dep_or_name)
        installer_set.remote = nil if spec.dependencies.none?
        Gem::Dependency.new spec.name, version
      elsif String === dep_or_name
        Gem::Dependency.new dep_or_name, version
      else
        dep_or_name
      end

    dependency.prerelease = @prerelease

    request_set.import [dependency]

    installer_set.add_always_install dependency

    request_set.always_install = installer_set.always_install
    request_set.remote = installer_set.consider_remote?

    if @ignore_dependencies
      installer_set.ignore_dependencies = true
      request_set.ignore_dependencies   = true
      request_set.soft_missing          = true
    end

    request_set.resolve installer_set

    @errors.concat request_set.errors

    request_set
  end
end
